1. Field of the Invention
The present invention comprises a wiring and tubing carrier for supporting line members such as wiring and/or tubing extending between a fixed structure and a movable structure, such as a slide-out room of a recreational vehicle.
2. Description of the Related Art
Recreational vehicles (RV's) often include a slide-out room which is movable between extended and retracted positions. The slide-out room remains retracted during transit of the vehicle and is extended when the vehicle is parked, to increase the usable floor space within the vehicle. Movement of the slide-out room is usually accomplished by an electric-motor acting through a gear drive, chain drive, or the like.
If the slide-out room includes electrically operated outlets or equipment, a gas stove or heater, or plumbing fixtures, some means must be provided for the orderly management of the wiring and/or tubing for such features during extension and retraction of the slide-out room. The wiring may include conductors for both low voltage (12V DC) and high voltage (110V AC). Plumbing may include water supply lines, as well as drain lines. Such lines must all be flexible. Additionally, such a wiring and tubing carrier must allow the wiring and/or tubing to flex as the slide-out room is extended and retracted, but must protect the lines from being pinched, stretched, or otherwise damaged.
In the past, wiring and tubing carriers for recreational vehicles have comprised a folding arm having two rigid sections of steel channel connected by a hinge joint. One end of the arm is hingedly connected to the main frame of the RV, and the opposite end of the arm is hingedly connected to the underside of the slide-out room so that the arm moves within a generally horizontal plane below the slide-out room. As the slide-out room is extended and retracted, the arm bends at the hinge joint. The channel is positioned with the flanges oriented inwardly toward the inside of the bend. The wiring and/or tubing is fastened to the arm sections, either inside the channel or on the back side of the channel, outside of the bend.
A problem with the folding arm type wiring and tubing carrier is that the hinge joint folds to a relatively sharp angle as the slide-out room is retracted, which can cause the wiring or tubing on the outside of the bend to be damaged by stretching. Wiring or tubing inside of the bend can be damaged by pinching. Gas lines are particularly susceptible to damage because they cannot be safely bent to less than a specific radius (such as 6 inches) depending on the hose configuration.
Wiring carriers having flexible support members are well known in applications other than slide-out rooms of recreational vehicles and trailers. For example, U.S. Pat. No. 6,501,020 to Grant et al. and U.S. Pat. No. 3,551,612 to Guentner both disclose a flexible wiring carrier for routing at least one cable from a first portion of an electrical equipment support system to a second portion of the system, wherein the first portion is movable relative to the second portion. The wiring carriers each comprise a flexible support strip extending curvilinearly between the first and second portions of the electrical equipment support system, wherein the flexible support member moves in conjunction with the movement of the first portion of the system. In both cases, the flexible support member remains connected between the first and second portions of the electrical equipment support system while the first portion moves.
The flexible support member of each patent has an upper edge extending continuously from the first portion of the equipment support system to the second portion. In both cases, substantially all of the upper edge remains disposed in a single horizontal plane while the flexible support member moves in conjunction with movement of the first portion. Both patents (U.S. Pat. Nos. 6,501,020 and 3,551,612) teach that the wiring carrier has at least one retention feature or retainer fixedly disposed along the flexible support member for supporting at least one cable. Both patents teach the flexible support member as being a generally uniformly flexible strip or belt which is disposed generally beneath the first portion of the support system.
In each of the devices disclosed by the Grant and Guentner patents, a first end of the flexible support member is rigidly connected to the first portion of the support system such that a respective first leg of the flexible support member remains, or is constrained to remain, oriented generally parallel to the direction of movement of the first portion, throughout the range of movement of the first portion. Similarly, a second end of the flexible support member is rigidly connected to the second portion of the support system, such that a respective second leg of the flexible support member remains, or is constrained to remain, oriented generally parallel to the direction of movement of the first portion throughout the range of movement of the first portion.
A problem that occurs with flexible support strips for wires and tubes, when both ends of the carrier strip are fixed in place, is that the strip may be stressed excessively unless the range of motion is limited for a given length of strip or the length of the strip must be increased for a given length of motion than might otherwise be necessary. Another problem with flexible strip type cable and tube supports is the volume of space which is occupied by the mechanism or which must be dedicated to clear the support-strip and supported wires and tubes from the retracted position through the extended position.